/*
//@HEADER
// ************************************************************************
// 
//                        Kokkos v. 2.0
//              Copyright (2014) Sandia Corporation
// 
// Under the terms of Contract DE-AC04-94AL85000 with Sandia Corporation,
// the U.S. Government retains certain rights in this software.
// 
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// 1. Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
//
// 3. Neither the name of the Corporation nor the names of the
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY SANDIA CORPORATION "AS IS" AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL SANDIA CORPORATION OR THE
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Questions? Contact Christian R. Trott (crtrott@sandia.gov)
// 
// ************************************************************************
//@HEADER
*/

#include <Kokkos_UnorderedMap.hpp>

namespace Kokkos { namespace Impl {

uint32_t find_hash_size(uint32_t size)
{
  if (size == 0u) return 0u;

  // these primes try to preserve randomness of hash
  static const uint32_t primes [] = {
        3, 7, 13, 23, 53, 97, 193, 389, 769, 1543
      , 2237, 2423, 2617, 2797, 2999, 3167, 3359, 3539
      , 3727, 3911, 4441 , 4787 , 5119 , 5471 , 5801 , 6143 , 6521 , 6827
      , 7177 , 7517 , 7853 , 8887 , 9587 , 10243 , 10937 , 11617 , 12289
      , 12967 , 13649 , 14341 , 15013 , 15727
      , 17749 , 19121 , 20479 , 21859 , 23209 , 24593 , 25939 , 27329
      , 28669 , 30047 , 31469 , 35507 , 38231 , 40961 , 43711 , 46439
      , 49157 , 51893 , 54617 , 57347 , 60077 , 62801 , 70583 , 75619
      , 80669 , 85703 , 90749 , 95783 , 100823 , 105871 , 110909 , 115963
      , 120997 , 126031 , 141157 , 151237 , 161323 , 171401 , 181499 , 191579
      , 201653 , 211741 , 221813 , 231893 , 241979 , 252079
      , 282311 , 302483 , 322649 , 342803 , 362969 , 383143 , 403301 , 423457
      , 443629 , 463787 , 483953 , 504121 , 564617 , 604949 , 645313 , 685609
      , 725939 , 766273 , 806609 , 846931 , 887261 , 927587 , 967919 , 1008239
      , 1123477 , 1198397 , 1273289 , 1348177 , 1423067 , 1497983 , 1572869
      , 1647761 , 1722667 , 1797581 , 1872461 , 1947359 , 2022253
      , 2246953 , 2396759 , 2546543 , 2696363 , 2846161 , 2995973 , 3145739
      , 3295541 , 3445357 , 3595117 , 3744941 , 3894707 , 4044503
      , 4493921 , 4793501 , 5093089 , 5392679 , 5692279 , 5991883 , 6291469
      , 6591059 , 6890641 , 7190243 , 7489829 , 7789447 , 8089033
      , 8987807 , 9586981 , 10186177 , 10785371 , 11384539 , 11983729
      , 12582917 , 13182109 , 13781291 , 14380469 , 14979667 , 15578861
      , 16178053 , 17895707 , 19014187 , 20132683 , 21251141 , 22369661
      , 23488103 , 24606583 , 25725083 , 26843549 , 27962027 , 29080529
      , 30198989 , 31317469 , 32435981 , 35791397 , 38028379 , 40265327
      , 42502283 , 44739259 , 46976221 , 49213237 , 51450131 , 53687099
      , 55924061 , 58161041 , 60397993 , 62634959 , 64871921
      , 71582857 , 76056727 , 80530643 , 85004567 , 89478503 , 93952427
      , 98426347 , 102900263 , 107374217 , 111848111 , 116322053 , 120795971
      , 125269877 , 129743807 , 143165587 , 152113427 , 161061283 , 170009141
      , 178956983 , 187904819 , 196852693 , 205800547 , 214748383 , 223696237
      , 232644089 , 241591943 , 250539763 , 259487603 , 268435399
  };

  const uint32_t num_primes = sizeof(primes)/sizeof(uint32_t);

  uint32_t hsize = primes[num_primes-1] ;
  for (uint32_t i = 0; i < num_primes; ++i) {
    if (size <= primes[i]) {
      hsize = primes[i];
      break;
    }
  }
  return hsize;
}

}} // namespace Kokkos::Impl

